Problem Statement
John had two sons called Tom & Cruise. They have two arrays a & b of length n. They had to reverse at most one subarray (continuous subsegment) of the array a. Their task is to reverse the subarray in such a way that the sum n∑i=1(ai⋅bi)is maximized.
Input
The first line contains one integer n (1≤n≤5000).
The second line contains n integers a1,a2,…,an(1≤ai≤107).
The third line contains n integers b1,b2,…,bn (1≤bi≤107).
Output
Print single integer — maximum possible sum after reversing at most one subarray (continuous subsegment) of a
In the sample example, you can reverse the subarray [3,5]. Then a=[1,8,3,6,7,6] and 1⋅5+8⋅9+3⋅6+6⋅8+7⋅8+6⋅6=235